Less hotkeys not working, printing keycodes instead performing action

php -i is doing something weird with stdin. Try this:

php -i </dev/null | less

Paused until further notice.

Posted 2011-03-14T23:16:36.307

Reputation: 86 075

Actually, it's less that does the "something weird". It changes to non-canonical mode input processing. Of course php may well be doing something as well, but this is simply a specific case of the more general don't have two programs simultaneously interacting with the terminal that employ different terminal input modes and expect things to work. – JdeBP – 2011-03-17T20:29:35.563

@JdeBP: less may very well be doing something weird, but this is from strace php -i without less: ioctl(0, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig icanon echo ...}) = 0 – Paused until further notice. – 2011-03-17T21:00:00.050

Setting canonical mode input processing (icanon) is not "something weird". Canonical mode is the norm. Hence its name. – JdeBP – 2011-03-18T13:44:04.380

1@JdeBP: Well, I don't know what's hidden behind the ... and perhaps the clue lies elsewhere. But why is php -i opening stdin at all? It does this same odd behavior with more (which is not a symlink or alias on my system), but, interestingly, not pg or (inconsistently) most. PHP also does this with php -r 'for ($i = 1; $i <= 100; $i++) { print "$i\n"; }' | less. AWK, Perl, Python, etc., don't exhibit this weirdness. Conclusion: PHP is broken. – Paused until further notice. – 2011-03-18T14:42:21.620

Less hotkeys not working, printing keycodes instead performing action

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